Religion is just a by-product of human evolution. Religion is just a by-product of psychology. Religion is surely nothing more than a by-product of some other, less-suspect field of human behavior. Such attitudes define religion in terms of another discipline, often to the chagrin of religious believers. But is this approach correct? Gregory R. Peterson (South Dakota State University) has recently argued those who try to reduce religion to the cognitive science of religion commit an important logical fallacy.